boulicault



NITED STATES PATENr tribe.

JEAN B. BOULIGAULT AND JOSEPH LEHNBEUTER, OF SI. LOUIS, MO.

FURNACE.

SPECIFICATION forming part of Letters Patent No. 335,176, dated February2, 1886.

Application filed March 2, 1883. Serial No. 86,797. (No model.) I

To all whom it may concern:

Be it known that we, J EAN B. BOULICAULT and J OSEPH LEHNBEUTER, both ofthe city of St. Louis, State of Missouri, have invented certain new anduseful Improvements in Furnaces, of which the following is aspecification.

The object of our invention is to obtain a of the furnace and its coursebroken as it rises by transverse bars, so that it may be warmed in itspassage, being finally introduced into the fire or combustion chamber atthe upper rear part thereof, and drawn over it toward the front by thedraft which is above the grate-bars and near the front of said chamber.

Our invention retains the general features of the Boulicault furnace;but for a more complete consumption of the smoke we have introducedcertain modifications and additions, intended to bring fresh jets orstreams of the external air into contact with the flames at a series ofpoints, so that they may always have a supply of oxygen until combustionis complete.

In the drawings, Figure 1 is a longitudinal section centrally through afurnace embodying our invention; Fig. 2, a second longitudinal sectionthrough the same furnace; Fig. 3, a vertical transverse section throughsaid furnace; Fig. 4, a second vertical'transverse section on adifferent line; Fig. 5, a horizontal section on the line 5 of Fig. 1,and Fig. 6 a second horizontal section on the line indicated bycorresponding number.

A represents the combustion-chamber of the furnace, covered by an arch,B B, which is pierced transversely, as in the above -mentioned patent,above the grate-bars and near the front wall, for the ventage orchimneydraft, but except at this point forms a close or imperforateceiling to said chamber.

0 are the grate-bars, placed at an inclination and removable, as in saidpatent, and O is any boiler, should one be used.

In front of the ash-pit G", lying transversely, is an air trunk, D,receiving'external air through a port, (1, at one side of the furnace,and extending substantially the whole width of said furnace,exposed tosome extent to the heat of the flames radiated through. the pit, so thatthe air therein may be raised in temperature in its passage. From thisair-trunk flues (1 lead through the brick-work at each side of theash-pit horizontally until they reach the rear of the pit, andare thencarried up vertically to the level of the grate-bars, when they returntoward the front, finally opening into the combustion-chamberimmediately under the arch close to the front wall of the furnace. Thisirregular course is given them that the air'may be raised still higherin its temperature by the heat radiated through the walls before itfinally enters the combustion-chamber. A third flue, (1*, leads from themain flue centrally along or beneath the floor of the ash'pituntil itreaches the rear, then rises and passes along the grate-bars above themtoward the front,where it becomes vertical, and discharges immediatelybeneath the crown of the arch. This flue, being surrounded by theburning fuel, will be bridged with fire-brick. The horizontal portion ofthe flue (1 also opens into the airduct E in the bridge-wall F at therear of the combustion-chamber, so that a current of air may be drawn uptherethrough, broken and retarded, and warmed as it goes, by thetransverse bars or bricks e, finally entering the combustion-chamberthrough a port, e, in the wall immediately beneath the arch. Heretoforethis latter air-supply has been introduced to the combustion-chamber orbrought 'into contact with the flames at only this single pointthat is,beneath the arch at the rear of the chamber. In our present invention wedivide it by a partition, f, depending within the duct, one portion ofit being conducted through the port in the bridgewall into thecombustion-chamber, and the second portion passing through the smallflues b in the rear section, B, of the arch, and discharging into theflames as they are drawn through the opening I) by the chimney-draft,but not at the combustion-chamber.

any other point, thus insuring that the air passing through these, fluesshall be highly heated, without, however, parting with any of its oxygenuntil the moment it strikes the flames rushing through the draftopening,when its effect will be expended and felt in the heating-chamber alone.

By the arrangement described We supply fresh air to thecombustion-chamber or to the flames at five different pointsfrom twoports at the sides of the chamber,from-a port at the front immediatelybeneath the crown. of the arch, from the vertical duct in the rear wallimmediately beneath the arch at the rear of the chamber, and from theseries of horizontal flues in the arch itself, the latter jets minglingwith the flames as they are rushing with great force through theconstricted opening in the arch under the influence of the chimneydraft.

The flues in the arch may be formed in-various ways. As shown in Fig. 4,they may be either square, rectangular in cross-section, or round, andit is apparent that the fire-bricks of which the arch is constructed maybe so shapedor molded that they will be formed by the simple setting ofsaid brick in constructing the arch. A damper, G, controls the inlet tothe air-trunk D, from which the various flues are supplied, so that theair-supply may be moderated or increased in all at once. If it isdesired to independently control the separate flues, they will each besupplied with dampers. They may also draw directly from the externalair, the purpose of the trunk be.- ing only to give the air-supply apreliminary warming, and to bring all the flues under the control of asingle damper. The irregular course given to the flues is partly forconvenience in construction and economyof space, but mainly to exposethem to the heat and cause the air passing through them to besufficiently raised in temperature before it enters Itpis therefore0bvious that their course may to. some extent be changed withoutdeparting from the principlev of our invention.

In saidformer patent there was no connection with the chimney, exceptthrough the opening in the arch. We find it desirable, to

connect with the chimney-draft at the rearof.

the combustion-chamber by asmall flue or. ventage, H, passing throughthe rear wall at this point, and a vertical duct, 71, into whichitopens, formed by the second bridge-wall, I, as.

shown. This leaves the, main draft still through the arch, but givessufficient-transverse draft to maintain the combustion of the fuel atthe rear of the grate-bars, which has heretofore been incomplete.

We. claim .as our invention 1-. The combination, in a furnace, of acombustion-chamber, a close arch crowning it, a draft-opening, throughsaid arch near. the

front of the chamber,-and air-portssupplying.

external air to said chamber at'the frontiand rear of the archimmediately beneath its crown,

said air'ports being fed from a flue or flues traversing the length ofthe furnace and exposed to the heat-rays.

2. The combination, in a furnace, of a combustion-chamber, a close archwhich covers it, a draft-opening through said arch, and airportssupplying fresh air to the chamber immediately beneath the crown of saidarch at front and rear, and also at each side of the chamber, saidair-ports being fed from a flue or flues traversing the length of thefurnace and exposed to the heat-rays therefrom.

3. The combination, ina furnace, of a combustion-chamber, a close archwhich covers it, a draft-opening through said arch, air-ports openingimmediately beneath the crown of the arch at front and rear, air-portsopening at the side of the chamber, and air-flues supplying external airimmediately at and transversely, along the draft-opening through thearch.

4. The combination, in a furnace, of a combustion-chamber, a close orimperforate arch which covers it, a draft-opening through said archnearthe front of said chamber, air-fiues passing longitudinally throughthe rear section of said arch and discharging immediately into thedraft-opening, and an air-trunk traversing the length of the furnace,and heated thereby, to aconnection with the rear of said fiues.

5. They combination, in a furnace, of a combustion-chamber, a close orimperforate arch Whichcovers it, a draft-opening through said arch nearthe front of said chamber, air-flues passing longitudinally through therear section of said arch and discharging immediately into saiddraft-opening, and an ascending airduct;.in the bridge wall at the rearof the chamber, supplying said flues at its head, and having aconnection at its foot with the externalxair.

6. The combination, in a furnace, ofa combustion-chamber, a close orimperforate arch which .covers it, a draft-opening through said archnear the front of said chamber, air-fines passing longitudinally throughthe rear section of said arch and discharging immediately intosaidzdraft-opening, an ascending air-duct in the bridge-wall at the rearof the chamber and supplying said flues at its head, and a connection atits foot with the external air, and transverse bars interrupting saidduct to retardthe, air-current as it rises to the flues in the arch.

7. The combination, in a-furnace, of a combustion-chamber, an archcovering it, a draftopening through said arch, an air duct orcompartment in the rear wall, an. opening fromsaidduct into thecombustion-chamber immediately beneath the rear of the arch,and-air-flues from said duct leading through the corresponding sectionof the arch to the draft-opening.

8. The combination, in a furnace, of an airtrunk laid transversely alongthe frontof the ash-pit, and an air-flue leading therefrom centrallybeneath the ash-pit, and returning up- 10. The combination,substantiallyas hereward to a discharge-port at the top and front inbefore set forth,of the transverse air-trunk, of the combustion-chamber. its damper, theside and central flues, the rear I 5 9. The combination, in a furnace,of an airair-duct, and the flues through the fine-arch. 5 trunk laidtransversely along the front of the ash-pit, a horizontal air-flueleading there- JEAN B. BOULIGAULT. from beneath the ash-pit to avertical duct in JOSEPH LEHNBEUTER. the rear wall of thecombustion-chamber, an air-port from said duct opening into the up-Witnesses:

10 per rear part of said chamber, and air -fiues F. M. ALLEMAND,

leading from said duct to the draft-opening FRANCIS HAMILTON.

or ventage.

